Excavator.



'No. 844,959. V PATENTED FEB. 19, 1907. M. 1). ROCHE-0RD.

EXGAVATOR.

APPLICATION FILED FEB. s, 1904.

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wr/ fwfd wwmmwmz PATENTED FEB. 19, 1907.

M. D. ROGHFORD.

EXGAVATOR.

APPLICATION FILED FEB.8,1904.

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No.844fl59. I I .PATENTED PEB.19,190T' M.D.ROOHFORD.;

BXGAVATORQ APPLICATION FILED FEB.8, 1904.

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No. 844,959; PA'IENTED FEB. 19, 1907. I M. n. 1100111 0111).

EXGAVATOR. APPLICATION FILED FEB.8, 1904.

4 SHEETS-SHEET 4.

7 UNITED STATES PATENT OFFICE.

MARK D. ROCHFORD, OF LOS ANGELES, CALIFORNIA.

EXCAVATOR.

To aZZ whom it may concern:

Be it known that I, MARK D. ROCKFORD, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Excavator, of which the following is a specification.

This invention relates to an excavator which employs buckets, scoops, or the like carried by an endless chain to perform the excavating-work and which is ada levees of all'descriptions, cellars, cleaning out silt or other deposit from irrigating-ditches, and, in fact, in all cases where the excavation extends through to the surface of the ground and earth is to be extracted from one point and deposited at another point.

The main distinguishing feature of the present invention is that .an endless chain is provided which carries the buckets or digging devices, and the chain is held in place by means of weights applied at opposite loops of the chain. The chain is thus balanced, so

to speak, and means are provided for controlling the balancing of the chain in such a way that the loop of the chain which is adj acent the digging may be caused to descend or ascend. Another object of the in"ention is to provide a novel and efficient conveyer for carrying the earth removed by the digging-chain from the machine and delivering it at a point removed from the machine and to so construct the conveyer that it will deposit earth at any point. desired within a considerable latitude and which, While depositing earth at practically one point, will permit the machine to move bodily. Another important and distinguishing feature is the provision of means'whereby the effective range or projection of the diggingloop of the chain into the earth may be altered without the necessity of changing the length of the chain.

Specification of Letters Patent. Application filed February 8, 1904- Serial No. 192,634.

ted to. make any excavation which exten s down Patented Feb. 19, 1907.

' Another distinguishing feature of the invention is that when in operation the digging is per rmed continuousl and the digging, remov a1, conveyance, an discharge of dirt is carried on also continuously simultaneously therewith. The digging-chain has a continuous movement through a definite orbit, during which the machine is advanced bodily,

so that the digging-chain is always held to the work-to be performed.

The action of the excavator maybe likened, 1n away, to that of a band-saw, the endless digging-chain having numerous scoops or buckets and being driven comparatively rapidly, each bucket or scoop removing but a comparatively slight amount of earth, but

the numerous buckets on the chain, comresulting in rapidly cutting. through the earth as the machine is advanced.

bined with the rapid movement of the chain, 1

1 The accompanying drawings illustrate the I invention, and, referring to the same, Figure 1 is'a side elevation of the excavator, showing it as set below the banks of a canal and digging out the bottom of the canal, the bottom of the canal being shown in section. Fig. 2 is a front elevation of the machine arranged as in Fig. 1, the earth adjacent the machine being shown in section transversely of the canal. Fig. 3 is a side elevation of the head portion of the conveyer. Fig; 4 is an end view of what is shown in Fig. 3. Fig. 5 is a plan view of the revoluble head which supports the head end of the conveyer. Fig. 6 1s a transverse sectional view taken on line X X", Fig. 1, somewhat enlarged. Fig. 7 is a side elevation of the follower-weight. Fig. 8 is a longitudinal section on line X X, Fig. 9. Fig. 9 is a front elevation of the followerweight. and adjacent portion of the diggerchains. Fig. 10 is a view similar to Fig. 9, showing the follower-weight as constructed for double digging-chains. Fig. 11 is an end elevation of the gearing and adjacent mechanism at the head end ofvthe conveyor, the conveyer being removed. In this vie'wthe lower part of the chain 63 is removed, together with its sprocket 62 the position which these (parts havein the foreground bein indicate by dotted lines. Fig. 12 is a sideelevation of what is shown in Fig. 11, part of the framework being sectioned. Fig.

13 is aside elevation'showing only the lower horizontally-arranged base-frame 1, which I may have suitable wheels 2, so that it. may be readily moved along, suitable planks 3 being laid down, so that the wheels will have 5 a smooth way over which to travel. The base-framework 1 supports a superstructure which comprises a vertical standard 4, composed of timbers 5, which are tied together at the top by cross-bars 6 and at an intermediate point by other crossbars 7. The upright bars 5 are further, secured in position and braced by truss-rods 8. Stability is given to the superstructure 4 by means of braces 9 and 10, the lower ends of which braces are secured to the base-frai'ne 1.

A cage or gear-carrier 11 is mounted upon the superstructure 4 for vertical adjustment up or down and comprises uprights 12, of which four may be provided, which are tied together by cross-bars 13. The cage 11 is suspended in posit-ion by a block-and-tackle arrangement 14, therope 15 of which is carried down from the upper block of the tackle over rollers 16 and 17, and its end is fastened 25 to a cleat 18.

A hoisting-engine 19 is mounted on the base-frame l, and when it is desired to raise or lower the cage 11 the rope 15 is attached to the hoist and the cage is thus raised or lowered to the desired oint,'after which the rope 15 may be given a fllw turns on the clcat 18 to hold the cage 11 in position, and this permits the operation of the engine 19 without disturbing the position of the cage 11.

Supported upon the lower cross-bars 13 of the cage 11 is a circular track 20, which has a diametrical web 21, forming a journal for a shaft 22.

23 is a revoluble yoke mounted above the track 20 and adapted to be turned around concentric with the shaft 22, having shoes 24,

which rest upon the upper face of the track- 20 and support the yoke 23 in such a manner that undue. friction between the yoke and track is avoided when the yoke it turned. A shaft 25 is mounted in one arm of the yoke 23 and carries a bevel-pinion 26,'which meshes with a bevel-gear 27, which latter'it mounted on the shaft 22. Thus the yoke 23 may turn 0 5 the face of the track 20 without disturbing the meshing of the two gears 26 and 27. A boom 28 is connected w1th the yoke 23 and carries a conveyor 29 for receiving and disposing of the earth elevated by the digging apparatus about to be describe 30 designates the endless digging-chain, which is supported at points intermediate its two loops by double sprockets 31 and 32.

The sprockets 31 are carried on a shaft 33,

which is mounted on cross-bars 13, while thesprockets 32 are carried on a shaft 34, which is also mounted on the cross-bars 13.

In the preferred construction I employ two chains arranged side by side, between which to any angle desired in a plane parallel with are arranged digging devices comprising buckets or scoops 35, spacedatsuitable intervals apart. it is obvious that the digging chain per 86 may consist of .but a single chain, the side links of which are spaced apart sufficiently to embrace the buckets 35,

and in referring to the digging-chain I mean a flexible connection carrying digging devices, Whether the flexible connection consists of a single chain to which the-buckets are attached or a double chain or a triple chain or any other form of flexible connec Between the scoops 35 I prefer to provide digging devices 36, which serve to breakupthe earth, so that the scoops 35 may the more easily scoop up the earth. The dig ging-chain is balanced by weights hung from both loops of the chain, and one reach of the chain is supported by sprockets 37, mounted on the shaft' 38, journaled in the cross-bars 13.- The chain is hung in such a Way that a certain portion of its length is sustained in a vertical position, the loop ofwhich is in serted in the ground at the point of eXcava-' 0 tion, and suspended by the loop is afollower- Weight 39, which serves to hold the vertical reaches of the chain taut and also produces a stable mounting for the devices which guide the chain around the loop.

Primarily the machine is designed for thecutting or excavating to be performed by the ascending vertical reach of the digging-chain but in some cases the digging will be per-- formed by thescoops'in their passage around the loop ofthe chain at the bottom. In-order to render the follower-Weight 39 more staple and hold the digging-chain more. firmly against the work and to prevent the follower-Weight from shifting from side to side, I provide a brace 40, which is pivotally attached to the follower-weight 39 and also geiribly attached to the base-frame 1 by a In cases where'the earth isvery soft orfriable and the cutting resistance comparatively little the brace 40 may be dispensed with but its employmentis advantageous" where the machine is put to severe use in cutting hard earth. g in order to maintain the digging-chain un-' der suflicient tension, and especially toikeep the ascending reach of the digging-chain firmly and unyieldinglyagainst the work, I- provide a balancing or tension weight which 120 is suspended tothe upperloop' of the diggingchain. The tension-weight may compnse a car 42, as shown, which may be filled with sand or other material and which is fitted with idler-sprockets 43, over which the dig- 12 5 ging-chain passes. The car 42 may ride upon an inclined track'or way 44, and the length of the way 44 is sufficient to permit of a certain amount of raising or lowering of-the follower-Weight. Its function is not prlmarily' 1 o for securing the different depths of excavation, but for giving the necessary movement of the car so that the chain may be always held taut. The depth of excavation is determined by shifting the cage 11 up or down. In operation the car 42 has a certain amount of play, caused by the automatic raising of the follower-weight when certain control ing devices, hereinafter to be described, have been actuated.

50 is a shaft mounted in brackets 51 ,whichare suspended from lower cross-beams 13 of the cage 11, and the shaft 50 carriesla bevelgear 52, which meshes with a bevel-gear 53 on the lower end of the shaft 22. The shatf 50 also carries a pulley 54, which is belted to the engine 19. T e shaft 50 also carries a friction-. pulley 55. It also carries a sprocket 56, which is connected by a chain 57 with a sprocket '58, mounted on the shaft 33.-

59 is a yoke pivoted by means of trunnions 60 to the framework of the cage. The yoke 59 supports a shaft 61, which. is out of center with the trunnions of the yoke, and mounted on the shaft 61 is a sprocket 62 which is connected by a chain 63 with a sprocket 64 on the shaft 34. Also mounted on.the shaft 61 is a friction-wheel 65, which is adapted to bear against the friction-wheel and which may be swung into or out of engagement therewith by slightly tiltin The shaft 61 is arranged wit respect to the trunnions of the yoke so that when the friction-wheel 65 bears against the frictionwheel 55 the shaft 61 will lie substantially in line with and between the trunnions of the yoke 59 and the'shaft 50. The yoke 59 is provided with a handle or lever 66, and a stron pressure between the friction-wheels may e secured by only a slight pull on the lever 66, owing to the arran ement just described. I prefer to normal y hold the two. friction-wheels in contact, and forthispurpose employ a coil-spring 67, which pulls upon the lever 66. "A rope 68 is attached to the end of the lever 66 and hangs down so as to be within convenient reach of the operator.

In operation the shaft 50 is driven from the engine 19 and through the medium of gears 52 and 53 drives the shaft 22. The shaft 33 is driven through the medium of sprocket 56, chain 57, and sprocket 58, while the shaft 34 is driven throu h the medium of the two friction-whee s, sprocket 62, chain 63, and sprocket 64 Thus the shaft 34 is driven in a direction opposite that of the shaft 33. As the shafts 33 and 34 are driven in opposite directions, the diggingchain 30 is continuously driven'in the direction of the arrow. By pulling the rope 68 and throwing the friction-wheel 65 out of engagement with the friction'.-wheel 55 it is obvious that the chain 63 will cease driving the shaft34 and that the chain 30 will only be the yoke 59.

driven by the sprockets which are mounted on the shaft 33. Under such circumstances the loop at the bottom of the diggin -chain 30 will be gradually raised and'thefo lowerweight 39 will be brou ht up as the shaft 34 remains stationary, an the tensionewei ht42 by its pull on the upper loop of the chaln, together with the friction and inertia of the shaft 34, its sprockets, and chain 63, and the sprocket 62, and shaft 61, is, combined, sufficient to prevent the turning of the shaft 34,

which causes the follower-weight 39 to. be drawn up. 1f the shaft 34 turns at a speed a trifle less than the shaft 33, the same result will be securedi. e., the lifting of the follower-weight 39; but the speed at which the follower-weight lifted would be less than when the shaft 34 was stationary. It is ob vious that the speed at which the followerweight rises will depend entirely on the difference between the speeds existing between shafts 33 and 34, the greatest lifting s eed of the follower-Wei ht being when the s aft 34 is stationary an the shaft 33 revolves at its highest speed, and said latter movement is that for which the machine is designed. When the follower-weight 39 is being lifted in the manner just described, the end of the brace 40 swings in a circular path, which forces forward the follower-weight 39 as the latter ascends, and the follower-weight is drawn out in a curved path, which causes the ascending reach of the diggin chain to be jammed against theearth. T is action of the follower-weight may be taken advantage of and utilized when for any reason the digging-chain seems to yield from the earth or does not work to its fullest capacity- When a cable 7i), which may be attached to some stationary object in the vicinity, as a stake 71, the other end of the rope 70 being wound up by the engine 19. 1

The cross-conveyer 29 comprises side beams/7 2, which-may have removable intermediate sections 73 whereby it maybe shortened. Beams 72 at one end carry a shaft 74 and at the other end carry a shaft 75. Pulleys 76 are mounted on both shafts 74 and 75, over I which runs a conveyer-belt 77. 'A sprocket 78 is mounted on the shaft 74 and is connected by a chain 79 with a smaller sprocket '80, mounted on the shaft 25, before described. The conveyer-belt 77 may be supported intermediate the pulleys 76 by rollers 81. The beams 72 aresupported at ISC ' out binding between the cross-bars 93. The

in a variety of ways. In Fig. 1. 3 of the drawthe machine end by brackets 82 and 83. (See Figs. 3 and 4.) The bracket 82' is hinged to one arm of the yoke 23, as shown in Fig. 4, while the bracket 83 has a concave notch, which rests upon the rounded upper end of the other arm of the yoke 23. By this means the conveyer is held from slipping ofl.

from the yoke 23 and its weight is borneby the yoke 23 directly.

The outer end of the conveyer may be supported by a bracket 84, which may be mounted on a sled 85 with a swivel 86. Thus the free end of the conveyer may be shifted by drawing along the sled 85, the swivel 86 permitting the necessary movement between the bracket 84 and sled 85, and the fixed end of the conve er readily swivels on the disk 20, as before d escribed.

, It is contemplated in actual work that the earth maybe delivered from the conveyer in.

one pile as the machine moves along. Of course as the machine advances the conveyer will be swung relatively to the machine, and its free end will gradually recede from its originalposition; but at the same time the earth as deposited Wlll be confined to sub-- stantially the same heap for a definiteamount of forward movement of the machine. f

A truss rod 87 may be employed to strengthen the side beams 72.

The followerweight may be constructed ings I have shown it as comprising a pendulous beam 90, at the lower end of whichis carried a shaft 91, upon which is mounted sprockets 92, over which the digging-chain runs. The weight is held in substantially a vertical position by means of two cross-bars 93,- between which the beam loosely passes, so that it may have considerable swing withlower end=of the beam 90 may be attached to a brace 94'- similarto the brace 40 previously described, and a convenienaway of adjusting the swinging radius of the brace 94 is to provide the brace..with notches 95, which may engage a cross-bar 96, while a slip-bolt 97 may be placed across the top-of the beam to I prevent it from jumping up and clearing the cross-bar 96. By withdrawi the slip-bolt 97 the beam 94-may readily e raised and shifted so that one or the other'o'f its notches will engage the cross-bar 96. The followerweight in another form (shown-in Figs; 7 to 9)' comprises side plates 100, which are united by a thick web 101, and in the side lates .at

the lower end of the Web is mounte .a'shatt 102,-upon which are mounted the sprockets 92,-over which the digging-chain 30 .rides.

The shaft 102 may-project a trifle beyond each face of the side plates 100, and rotating gipider diggers 103 may be employed. A 1 have two of its arms equippedv with plain points 104, while two other'of its arms maybe equipped with blades 105. The

gger 103 may dig ing-chain may carry a double row of buc :ets, as shown, the follower-weight being slightly modified in construction.

The function of the machine does notwholly reside in making excavations to the exclusion of other important uses to which it may be put, and, while the machine hasbeen termed an excavator on account of 1ts predominating adaptability as such, such special adaptability in no wise negatives its e'l'liciency for performing work other than pure excavating. For instance, in cleaning canals having a high bank on the other side of which earth from the bed is to be deposited the machine may remainEstationary, with its conveyerex'tending over the high bank, and the earth from the bed may be transported to the digging-chain by wagons or scrapers and elevated by the buckets on the digging-chain to the conveyer and thence carried over the bank, obviatin the heavy duty required to carry the earth over ahigh bank by teams; In such cases the digging-chain acts purely as an elevator:

What I claim is 1. An endless chain, digging devices on the chain, means for driving the chain, and a weight for holding the chain in digging position. i 2. An endless chain, digging devices on the chain, and means for suspending the chain at a point intermediate its loops.

3. An endless chain, digging devices on the I chain, means for suspending the chain at a point intermediate its loops, and means for balancing the chain.

4. An'endless chain, digging devices on the chain, means for suspending the chain at a point intermediate its loops, and a followerweight hung in one loop. a

' 5. An endless chain, diggingdeviceson the chain, means for suspending the chain at a point intermediate its loops, a followerweight hung in one loop, and atensionweight hung in the other loop.

6. An endless chain, digging devices on the chain, 'and means engaging both reaches of the chain intermediate its loops for driving the same. 2

7. An endless chain, digging devices on the chain, and means for driving one reach'faster than-the other to change the position of the chain and driving the chain, and means for.

vertically adjustingthe last-named means.

10. An endless chain, scoops on the chain,

means for supporting and driving the chain, a weight for holding the chain stiff-looped,

and means for moving the chain bodily vertically.

11. An endless chain, scoops on the chain, means for supporting and driving the chain, a weight for holding the chain stiff-looped, and means for moving the chain bodily horizontally.

12. An endless chain, scoops on the chain, means for supporting and driving the chain, a Weight for holding the chain still-looped, means for moving the chain bodily horizontally, and means for moving the chain bodily vertically.

13. An endless chain, the chain, means for driving the chain, and yielding means for holding the chain in digging position.

14. An endless chain, digging devices on the chain, means for suspending the chain at a point intermediate its loops, and means for i yieldingly holding both loops taut.

15. An endless chain, digging devices on the chain, means for suspending the chain at a point intermediate its loops, and yielding loop of the chain means engaging the upper for balancing the chain.

16. An endless chain, digging devices on the chain, means for suspending the chain at a point intermediate its loops, yielding means digging devices on 3 for balancing the chain, and means for varying said balance to rotate said loop without disturbing the other loop.

17. An endless chain, digging devices on the chain, means for suspending the chain at a point intermediate its loops, means for yieldingly holding both loops taut, and means for shortening one loop and simultan'eously lengthening the other loop.

18. A loop, sprockets supporting said loop, means for vertically moving sai sprockets, and means for driving the chain.

19. An endless chain, means or supporting said chain in two loops one of which is vertical and the other is inclined, and digging devices on the chain.

20. A pair of loops, buckets carried thereby, means for driving said chain, and means at the end of each of said loops for holding both of said loops taut.

signed my name, in the presence of two subscribing witnesses, at Los Angeles, in the county of Los Angeles and State of California, this 29th day of January, 1904. i MARK D. ROCHFORD \Vitnesses:

Gnoncn T. HAGKLEY,

JULIA TOWNSEND.

In testimony whereof I have hereunto 

